In an article about high-altitude airships being developed by Lockheed Martin for the US Missile Defence Agency (Is the US launching a blimp to spy on its population?, Technology, page 2, January 25) we said each airship could oversee an area of 600 square miles. That should have been an area with a diameter of 600 miles.

Contrary to what we said in Psst! Have you heard?, pages 7 to 11, G2, yesterday, Microsoft did not buy Hotmail until late December 1997, and the marketing campaign referred to had nothing to do with Microsoft. It was because of Hotmail's success in attracting users that Microsoft then purchased the service. In the same article, Proctor & Gamble should be Procter & Gamble.

There were several mistakes in a column headed I want my body back, page 17, G2, yesterday: the company is called Pushy Mothers, not Pushy Mums; it is Judy DiFiore, not Fiore; the website is www.pushymothers.com not www.pushymums.org

Rose Hacker, the centenarian mentioned in Are you clever enough to live here?, pages 4 and 5, Family, January 27, is a columnist on the Camden New Journal newspaper (for whom she writes two columns a month), not the Hampstead & Highgate Express.

In a column, Quiz con ought to have put ITV in the rogues' gallery, page 4, Media, January 29, we said calls to these shows cost 75p a minute. In fact, they are charged at a flat rate of 75p. The calls sometimes last only 2 or 3 seconds but callers are still charged.

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